Spool retarding brake device for axminster looms



Feb. 16, 1937. LA FRANCE SPOOL RETARDING BRAKE DEVICE FOR AXMINSTER LOOMS Filed April 5, 1936 INVENIOR l e/mes [A fkwc:

ATTORNEYS Patented Feb. 16, 1937 UNITED STATES.

SPOOL RETARDING BRAKE DEVICE FOR AXlVIINSTER LOOBIS Horace La France, Springfield, Mass., assignor to Hodges Carpet Company, Inc., Indian Orchard, Mass, a corporation of Massachusetts Application April 3, 1936, Serial No. 72,476

1 Claim.

This invention relates to an improvement in brake device for the yarn spools of the tuft supply frames used in Axminster looms and the like.

In looms of this character, as is well known in the art, a large number of these tuft supply frames are releasably supported in parallel relation between intermittently moving chain conveyors. The frames are successively detached from the chains, during the dwell in the travel of the latter, and moved by the usual transfer device to bring the yarn ends to delivery position; It is desirable that a relatively light and uniform braking action be applied to the spools on the frames to retard their rotation and apply a slight tension to the yarn as the latter is drawn off for incorporation in the carpet or other fabric being produced.

The means for applying this braking or retarding action now commonly in use comprises a leaf spring member secured at one end by screws to the frame, the free end being provided with a pad or square of friction material which bears against the flanges on the outer ends of the end spools of the spool assembly on the frame. An example of this prior type of braking means is shown in the patent to Hathaway et al. 1,594,- 880, issued August 3, 1926.

' The leaf spring type of braking means above mentioned has several disadvantages. Among these is the fact that the braking pressure depends on the initial angle of the spring and slight variations at the point of attachment are magnified at the free end where the braking pressure is applied. There is also a substantial amount of time consumed in replacing the brakes which must be done when the friction pads become worn. A further objection is that since the friction pad moves in an arc about the point of attachment of the spring the pressure is not uniform against the flange of the spool. In other words, due to the physical characteristics, shape and method of attachment of said leaf spring brake devices it is difficult to obtain a satisfactory degree of uniformity in the braking action cordance with the pattern to be woven. The desideratum is tohave all the spools exhausted of yarn when a predetermined length of fabric is completed, because when any appreciable-number of spools run out of yarn all the spools of the chain must be replenished to prevent irregularities in the pattern. I Consequently a nonuniform braking action on the several spools will permit some to exhaust their yarn before others, and the remnant of yarns on the nonexhausted spools becomes waste. To avoid this waste I have devised the present form of braking device which I have found in practice may be made to apply a substantially uniform braking action on each of the several hundred spools in the chain, a result which so far as I know has never been accomplished with the devices heretofore employed.

I am aware that it has been proposed to employ brake means in which the braking pressure is applied radially by means of coiled springs but the prior art structures of this character have not proved practical because of their cost, the relatively complicated structure involved, and the fact that it required a longer time to replace them, both in removing the worn device and installing a new one.

It is the principal object of my invention to provide a radial acting brake device which is simple in structure, reasonably comparable in cost to the prior flat spring braking means, and which can be easily removed or installed in less time than prior art structures.

Other and further objects will be apparent from the following specification and claim.

In the accompanying drawing which illustrates one embodiment,

Fig. l is a front elevation of a frame or carrier equipped with the braking means of my invention;

Fig. 2 is a transverse View showing the frame and parts of the brake means in section; and

Fig. 3 is a. side elevation of my brake device removed from the frame.

Referring to the drawing, the tuft supply frame comprises the hollow carrier bar I provided with end support 2 and intermediate supports 3 by which the yarn spools, which are indicated at 4, are rotatably mounted on the frame. The supports 3 and 2 are of conventional construction, the intermediate supports 3 providing for a splined connection between the spools so that braking action applied to the outer flanges 5 of the end spools acts to retard the rotation of all three spools. The spools are of course removable from their supports. Since these supports form no part of my invention and may be of any conventional pattern further description thereof is unnecessary. The frame I is provided at its ends with means indicated at 6 for connecting the frame to the conveyor chains, not shown, of an Axminster loom. The connect ing means 6 may be likewise of conventional structure and therefore need no further description.

The carrier bar I, as is clear from Fig. 2, is formed of tubular material, rectangular in cross section. The carrier bar is provided on its upper face, adjacent each of its ends, with openings 1 which are positioned beneath the end flanges 5. These openings 1 receive my improved brake means as later described.

The braking device comprises an outer cylindrical casing 8 open at its upper end and formed with an inwardly extending flange 9 at its lower end to provide a restricted opening Ill. The upper end is constructed with an outwardly extending flange I l. A plunger having a cylindrical head l2 and a shank l3 fits within the casing 8, the head I2 being of a diameter to slidably engage within the casing with the shank extending through the opening II]. A coiled Spring I5 is positioned in the casing surrounding the shank 3 and having its upper and lower ends respectively engaging the head l2 of the plunger and flange 9 of the casing. The free end of shank I3 is provided with a Washer-like member '16 which is welded or otherwise secured to the shank outwardly of the casing after the plunger, spring and casing have been assembled, member l6 thus forming a stop which limits the upward movement of the plunger in the casing under the influence of the spring 15. A brake shoe comprising a friction pad l6 of leather, or other suitable material, and a curved backing plate I7 is secured to the upper end of head l2 by a rivet 18 or other suitable securing means.

The diameter of opening I, in relation to the outer diameter of casing 8, is made such that the casing may be driven into opening I to make a tight friction fit.

It will be seen that my brake device consists of only four main parts, namely the plunger with its brake shoe, the casing 8, spring l5 and member IS. The device is assembled by inserting the plunger and spring in the casing and securing them in position by the application of member l6. So assembled the device is a selfcontained unit, quickly and easily put in operative position in the frame by driving it into opening 1 until flange H engages the face of the frame I. The unit is as easily removed with a pair of pliers When replacement is necessary.

It should further be noted that the size of the spring and the dimension of the parts are easily made uniform and the spacing of the device relative to the spool flange 5 is determined by flange H so that the braking force of pad l6 against the flange 5 is uniform and radially applied. The cost of manufacture of my device is reasonably comparable with that of the prior leaf spring structures. The braking action does not substantially vary from one device to another. It may be noted in this connection that the spring is confined-between members of the device itself and is completely enclosed in the casing affording protection against lint and dust. Furthermore, as is evident from the above description, the time involved in replacing a worn out device is very materially lessened, substantially reducing the period of shut down which is an important factor in the economical operation of these looms.

I claim:

In combination, a tuft supply frame comprising a hollow carrier bar provided with means for rotatably supporting thereon a flanged yarn spool, the upper wall of said hollow bar having an opening therein to provide a receptacle for a brake unit adapted to act radially against the spool flange, said brake unit comprising a cupshaped case snugly fitting into said receptacle opening for being slidably removed therefrom, and having an outwardly flanged rim to limit the movement of said case into said receptacle opening when inserted therein, a plunger slidably mounted in the casing and provided on its upper end with a brake shoe adapted to bear against said spool flange, spring means confined within the casing between the plunger and the bottom of the casing to urge the plunger outwardly of the casing and means to limit the movement of the plunger outwardly and upwardly of the casing.

HORACE LA FRANCE. 

